The present invention generally relates to an exercise device for use by a person while training along an arcuate path. The present invention also relates to an exercise device for a person wearing skates that allows the person to train and exercise at a proper height and orientation and in a balanced stance during either static or dynamic training or exercising activities.
Persons who wear skates, such as ice skates and roller skates, and persons who wear skis, such as water skis and snow skis, have been able to train and exercise using a variety of training aids and exercise devices. These aids and devices typically permit the person to learn correct body orientation and balance and also help develop muscle groups required for the skating or skiing activity.
One example of an existing training apparatus is disclosed in U.S. Pat. No. 4,340,214 to Schutzer. The Schutzer device is similar to the slideboard which is well known among serious skaters. The Schutzer device provides a lateral inclined track which allows side-to-side motion and stretching of the feet and legs. An upright support at the center of the Schutzer device helps maintain the user's body in the correct skating position.
U.S. Pat. No. 4,915,373 to Walker discloses an exercise machine for developing ice skating skills. The Walker machine includes a bicycle-type saddle in the center for seating the user in a crouching position. Foot stirrups that are intended to approximate the skating motion ride in two triangular tracks on either side of the saddle. A portion of each track is designated as a power section and is provided with means for creating drag on the stirrups as the stirrups pass through the power section. The drag created by passage of the stirrups through the power section requires greater exertion of force by the user to move the stirrups through the power section.
U.S. Pat. No. 5,284,460 to Miller discloses a device that is similar to the Walker and Schutzer devices. The Miller device is essentially a stationary training device with a central support that is located behind the skater. The central support allows the skater's trunk to remain in a fixed location in relation to the central support while allowing the skater to freely move his or her feet in a side-to-side skating motion.
U.S. Pat. No. 5,385,520 to Lepine discloses a treadmill for practicing ice skating techniques while permitting close range observation of the skating technique in a controlled off-ice environment. The treadmill includes a motorized, rotating, endless belt that offers the skater a stationary platform for developing skating technique. The artificial environment of the Lepine device assists the user in developing either forward or backward skating technique, but does not address techniques for skating along an arcuate path. Additionally, the artificial environment does not allow the skater to practice skating techniques on a real-live skating surface, such as ice or land.
The act of wearing a pair of skates or skis produces the advantage of reduced friction with the skating or skiing surface so that the person wearing the skates or skis can glide across the surface. The reduced friction permits skaters and skiers to use less energy in producing and maintaining the momentum needed to glide across the skating or skiing surface.
The inherent difficulty with skating and skiing is that the reduced friction often accelerates unbalanced movements when the person's center of gravity is not balanced directly over the person's feet and helps cause the person to fall. To avoid unbalanced movements, the person must quickly and correctly move the feet, while maintaining proper body stance, to counteract the forces causing the unbalanced movements. Vulnerability to failing is especially pronounced in persons who are first learning how to ski or skate. Also, more advanced skiing and skating techniques that require shifting the body's center of gravity to a position that is not directly over the feet often produces a loss of balance if the center of gravity is not quickly and correctly shifted in a coordinated movement.
These problems relating to adequate control of the body's center of gravity exist when the skater or skier is learning to move forward and are even more pronounced for persons who are learning to move backward. Also, skaters and skiers who are learning to turn, corner, or otherwise move along an arcuate path often experience problems relating to adequate control of the body's center of gravity.
Some of the forces that act on a person who is skating or skiing along an arcuate path are centrifugal in nature. The centrifugal forces acting on the person are applied to the person's center of gravity and produce a moment about the point where the skate blade or wheel contacts the skating surface or where the ski contacts the skiing surface.
This moment produces a rotational acceleration of the individual that may force the skate blade, skate wheel, or ski to deviate from the arcuate path and may also cause the person to lose his or her balance and fall. In order to continue traveling along the arcuate path without falling, the individual must counteract the centrifugal force by applying a counterbalancing force to the skate blade, skate wheel, or ski. The counterbalancing force should be oriented directly to the center point that defines the arcuate path or arcuate path segment.
There is a need for a device that allows skaters and skiers to learn and perfect proper body orientation and positioning and proper techniques for applying forces that counterbalance centrifugal forces encountered when skating or skiing along an arcuate path. No existing device, including the aforementioned Schutzer, Walker, Miller, and Lepine devices, permits persons of all experience levels--from beginner to expert--to train in a dynamic environment while learning and perfecting the proper body orientation, positioning, and force application needed when skating or skiing along an arcuate path.
One make-shift technique for teaching arcuate path travel does exist. This technique involves a trainer who stands at the center of a radial path. The trainer holds onto one end of a hockey stick or a ski pole and stands at the center of a radial path. The skater or skier holds onto the other tend of the stick or pole and skates or skis about the trainer along the radial path. This technique is of limited usefulness because the trainer standing at the center of the radial path rotates with the skater or skier and quickly becomes tired, dizzy, and disoriented.
A need also exists for a device that allows a stationary skater or skier to learn proper body orientation and positioning for applying correct counterbalancing force. Such a device would permit a trainer to demonstrate discreet elements of the proper skating technique and to observe and modify particular aspects of the person's skating or skiing technique in a controlled environment.